1. Field of the Invention
The present invention relates generally to a light source lamp, and more particularly to a light source lamp having an internal seal for sealing the lamp envelope about the electrodes.
2. Description of the Prior Art
Various light source lamps, e.g., arc lamps and flash lamps, exist in the prior art. In manufacturing light source lamps, a problem to be overcome is to provide an economical seal between the electrical feed through and the lamp envelope while also producing a reliable high voltage insulation system to prevent high voltage arcing to adjacent metal structures and lamp-mounting surfaces.
The prior art includes both inside and outside seals with indium based solder and high temperature glass or quartz envelope-to-tungsten seals. Seals made on the outside diameter of a quartz envelope commonly have a disadvantage in that the high voltage insulation system is difficult to design and manufacture in the available space. High temperature quartz-to-tungsten seals have the disadvantage of being brittle and require highly skilled technicians to fabricate the seals. The difference in the coefficients of expansion of the envelope material and the metal pose difficulties with the varying temperatures.